Sampling pumps and gas analyzers

ABSTRACT

Provided are sampling pumps and gas analyzers using the sampling pumps. The sampling pump may include at least one reciprocating pump set and a control system. Each reciprocating pump set can include two reciprocating pumps. The control system can output drive signals for controlling reciprocating drawing and compressing operations of the reciprocating pumps, where the control system may be designed to output the drive signals that cause the two reciprocating pumps within the same set to provide opposing impact directions at the same time.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/334,429, filed Jul. 17, 2014, for SAMPLING PUMPS AND GAS ANALYZERS,which is a continuation of Patent Cooperation Treaty Application No.PCT/CN2012/087485, filed Dec. 26, 2012, which claims the benefit ofpriority to Chinese Patent Application 201210018139.X, filed Jan. 19,2012, each of which are hereby incorporated by reference.

TECHNICAL FIELD

This disclosure generally relates to respiration monitoring in themedical field and particularly to sampling pumps and gas analyzers usingthe sampling pumps.

BACKGROUND

Sampling pumps that are widely used for respiration monitoring inmedical equipment or modules, such as gas measurement modules, canextract a gas sample from a patient's breathing circuit and convey theextracted gas to respiration monitoring equipment, so that therespiration monitoring equipment can monitor the composition of the gasexhaled by the patient in real time, thereby allowing medical staff toevaluate the patient's vital signs. The gas sensor probe for gasmeasurement used in respiration monitoring equipment is a precisioninstrument, and its measurement accuracy can be affected by vibrationalinterference that may be present during operation. The sampling pump isoften a main vibration source in the respiratory monitoring module. Thegas sensor can also be sensitive to flow fluctuations of the monitoredgas. If the gas sensor experiences large flow fluctuations, somemeasurement noise may occur, which can also affect measurement accuracy.Therefore, the sampling pump should provide stable sampling flow.

A diaphragm sampling pump using a single rotary motor is often used forgas sampling in existing respiration monitoring equipment. Due to itsworking principle, the diaphragm pump usually has both relatively largeflow fluctuations and some vibrations during sampling. A single linearreciprocating pump may produce larger vibrations, and thus it is nottypically used in respiration monitoring equipment.

SUMMARY OF THIS DISCLOSURE

This disclosure provides sampling pumps for delivering fluid andreducing vibration and provides gas analyzers for gas detection andanalysis that use such sampling pumps.

In one aspect, a sampling pump may include at least one reciprocatingpump set and a control system. Each reciprocating pump set can includetwo reciprocating pumps. The control system can output drive signals forcontrolling reciprocating drawing and compressing operations of thereciprocating pumps, where the control system may be designed to outputthe drive signals that can cause the two reciprocating pumps within thesame set to provide opposing impact directions at the same time.

In some embodiments, the two reciprocating pumps can be fixedly mountedin such a way that the impact directions generated by the tworeciprocating pumps may be along the same line (i.e., a common line).

In some embodiments, the two reciprocating pumps within the same set canbe linear reciprocating pumps with the same or substantially the sameimpact force.

In some embodiments, the two reciprocating pumps within the same set canbe rigidly fixed along the same line and in the same orientations. Thedrive signals provided to the two reciprocating pumps can have the sameamplitude and a phase deviation of about 180°.

In some embodiments, the two reciprocating pumps within the same set canbe rigidly fixed along the same line and in opposing orientations. Thedrive signals provided to the two reciprocating pumps can have the sameamplitude and phase.

In some embodiments, the two reciprocating pumps within the same set canbe directly, rigidly and fixedly connected to each other to form anintegral structure.

In some embodiments, the sampling pump may also include at least oneconnection carrier, where the two reciprocating pumps within the sameset can be rigidly and fixedly mounted on the same connection carrier.

In some embodiments, the connection carrier may be a connection platethat is affixed to side surfaces of the reciprocating pumps.

In some embodiments, the sampling pump may also include at least oneintegrated output channel. The integrated output channel can communicatewith output channels of the two reciprocating pumps within the same setso as to gather fluid outputted from the two reciprocating pumps withinthe same set.

In another aspect, a gas analyzer may include a gas measurement modulefor detecting and analyzing some extracted gas, and a sampling pumpdescribed above for providing the gas measurement module with the gas tobe measured.

In some embodiments, the gas analyzer may also include a gas circuit,where the gas circuit can include at least two gas outlets and at leastone integrated output channel. The two gas outlets can communicate withthe integrated output channel, and output channels of the tworeciprocating pumps within the same set can communicate withcorresponding gas outlets.

BRIEF DESCRIPTION OF THE DRAWINGS

The following detailed descriptions of respective embodiments in thisdisclosure can be understood better when combining with these figures,in which the same structure is represented by the same reference sign.In the figures:

FIG. 1 is a schematic diagram showing the locations of two linearreciprocating pumps in accordance with an embodiment of this disclosure;

FIG. 2 is a schematic diagram showing the orientations of two linearreciprocating pumps in accordance with an embodiment of this disclosure;

FIG. 3 is a schematic diagram showing the orientations of two linearreciprocating pumps in accordance with another embodiment of thisdisclosure;

FIG. 4 shows a structure in accordance with an embodiment of thisdisclosure; and

FIG. 5 shows a structure in accordance with another embodiment of thisdisclosure.

DETAILED DESCRIPTION

This disclosure is further described below in detail with reference tothe figures and specific implementations.

In various embodiments of this disclosure, a sampling pump may includeat least one reciprocating pump set, where each reciprocating pump setmay include two reciprocating pumps that are fixedly mounted along thesame or common line. Herein, the two reciprocating pumps within the sameset can provide impact forces in opposing directions at the same time byconfiguring drive signals used to control reciprocating drawing andcompressing operations of the reciprocating pumps, so that the impactforces caused by the movements of the reciprocating pumps can becounter-balanced and some vibrations correspondingly generated can bereduced.

The reciprocating pump in this disclosure can be a rotary motorreciprocating pump driven by a rotary motor, and it can also be a linearreciprocating pump driven by a driving device capable of outputtinglinear reciprocating movement directly. For example, a diaphragm pumpusing a voice coil linear motor or any other driving device capable ofoutputting linear reciprocating movement can be used as the linearreciprocating pump. Two reciprocating pumps within the same set can befixedly mounted along the same line, as a result of which the impactforce that is generated by one reciprocating pump when acting onfluid(s) can be transferred and applied to the other reciprocating pump.Through further regulation and/or control, the two reciprocating pumpswithin the same set can provide opposing impact directions at the sametime, so that their respective impact forces may be completely or mostlycounter-balanced, and thus some vibrations caused by the impact forcesof the reciprocating pumps during their operation can also becounter-balanced, thereby ensuring stable operations of thereciprocating pump set and the sampling pump using the same. Herein, thefluid(s) can be a gas, liquid or mixture thereof.

In an embodiment, the two reciprocating pumps within the same set can berigidly and fixedly connected with each other so as to transfer theirimpact forces and vibrations. In some cases, the two reciprocating pumpscan be directly and rigidly fixed together to form an integralstructure. In some cases, the sampling pump can also include a thirdconnection carrier such as a connection plate, a base or the like, wherethe two reciprocating pumps can both be rigidly and fixedly mounted ontothe third connection carrier.

The two reciprocating pumps within the same set can be arranged next toeach other, so that their respective impact forces can be at leastpartially counter-balanced. In an embodiment, the two reciprocatingpumps within the same set are arranged next to each other and along thesame line. In this case, the impact forces and the vibrations generatedby the two reciprocating pumps can be maintained along the same line tocounteract with each other. Referring to FIG. 1, A represents a frontlinear reciprocating pump, and B represents a rear reciprocating pump,while the pumps A and B are arranged on the same straight line. Thearrows in FIG. 1 refer to impact and vibration directions generated bythe linear reciprocating pumps. When a control system controls the pumpA to generate leftward or rightward impact force, the control system maycorrespondingly control the pump B to generate impact force in anopposing direction (i.e., rightward or leftward respectively), in whichcase their respective impact forces can completely, substantially orpartially counter-balance with each other.

The two reciprocating pumps within the same set are required to provideopposing impact directions at the same time. For this purpose, thecontrol system can send drive signals having coordinated drivingcommands to the two reciprocating pumps so as to control theirrespective drawing and compressing timings. The drive signals can becurrent signals, voltage signals or any other suitable signals.

Using the case where the two reciprocating pumps are both linearreciprocating pumps as an example, since linear reciprocating pumps maybe directly driven by a driving device capable of outputting linearreciprocating movements, the control system can send drive signals thathave the same amplitude(s) as well as the same or opposing phase(s) tothe two linear reciprocating pumps, so that the driving devices insidethe two linear reciprocating pumps can achieve coordinated operations.

In an embodiment, the two linear reciprocating pumps within the same setare both rigidly fixed along the same line and mounted to have the sameorientations. The impact forces respectively generated by the two linearreciprocating pumps during their drawing and/or compressing operationscan be the same (or substantially the same), or can have an allowabledifference within a specified range (the specified range can be manuallyset according to actual needs). Here, the orientation of thereciprocating pump refers to a movement direction outputted by thedriving device inside the reciprocating pump when fluid is compressedout of the reciprocating pump. For example, the arrows in FIG. 2respectively represent the movement directions outputted by the drivingdevices inside the two linear reciprocating pumps when fluid isrespectively compressed out of both linear reciprocating pumps. In thisembodiment, the directions shown by the arrows can be defined as theorientations of the linear reciprocating pumps, where the two linearreciprocating pumps have the same orientations as shown in FIG. 2. It isnoted that when the fluid is drawn into the linear reciprocating pump,the movement direction outputted by the driving device inside the linearreciprocating pump is opposite to the orientation of the linearreciprocating pump. In this embodiment, the two linear reciprocatingpumps within the same set may often be equally designed in their impactresponses, and their drive signals may also be the same in amplitude.Therefore, when the fluid is drawn into or compressed out of the twolinear reciprocating pumps under the control of the drive signals, theimpact forces generated from the movements of the two linearreciprocating pumps can also be the same (or substantially the same).Here, the drive signals with alternative directions can be transmittedfrom the control system to the two linear reciprocating pumps; that is,those drive signals that have the same amplitudes and the opposingphases (i.e., with a phase deviation of about) 180° can be respectivelyprovided to the two linear reciprocating pumps. Under the control of thedrive signals, the driving device inside one of the two linearreciprocating pumps may move to the left while the driving device insidethe other linear reciprocating pump may move to the right, and viceversa; that is, one of the two linear reciprocating pumps is drawing thefluid while the other one is compressing the fluid out, and vice versa.The movement directions of the driving devices inside the two linearreciprocating pumps are maintained to be opposite to each other at anytime. In this way, the impact vibrations generated by the two linearreciprocating pumps along opposing directions can counter-balance witheach other, and thus stable operation can be achieved for the samplingpump.

In another embodiment shown in FIG. 3, the arrows respectively representthe movement directions outputted by the driving devices inside the twolinear reciprocating pumps when fluid is respectively compressed out ofboth linear reciprocating pumps. Here, an arrow also indicates theorientation of a linear reciprocating pump, and thus the two linearreciprocating pumps in this embodiment may have opposing orientationsrepresented by the opposing arrows. Also as discussed above, when somefluid is drawn into the linear reciprocating pump, the movementdirection outputted by the driving device inside the linearreciprocating pump is opposite to the orientation of the linearreciprocating pump. In this case, the control system may send the samedrive signals (i.e., with the same amplitude and phase) to the twolinear reciprocating pumps, so that the two linear reciprocating pumpscan have the same drawing and compressing timings. That is, when one ofthe linear reciprocating pumps is drawing the fluid, the other linearreciprocating pump is also drawing the fluid. In this situation, sincethe two linear reciprocating pumps have opposing orientations, themovement directions outputted by their internal driving devices can beopposite to each other, and thus the impact vibrations may also begenerated in opposing directions. Therefore, such impact vibrations cancounter-balance with each other, thereby achieving stable operation forthe sampling pump.

When a rotary motor reciprocating pump is in operation, its outputcomponent (such as plunger or piston) may also generate somereciprocating impact when acting upon fluid. In an embodiment, thecontrol system can be used to output the drive signals to two rotarymotor reciprocating pumps to control the rotation timings of the rotarymotors inside. In this way, the timings for linear reciprocatingmovements can be adjusted for the output components inside thereciprocating pumps.

In some embodiments, the reciprocating pump set can include one linearreciprocating pump and one rotary motor reciprocating pump.

In an embodiment, output channels (i.e., fluid outlets) of the tworeciprocating pumps within the same set can be assembled together toform an integrated output channel. The integrated output channel cancommunicate with the output channels of both reciprocating pumps withinthe same set, and thus the fluid may be outputted through the integratedoutput channel uniformly. When the two linear reciprocating pumps havethe same orientations and their output channels are assembled into theintegrated output channel, the fluid flow resulting from the two linearreciprocating pumps may be stable with substantially no fluctuations byforming peak-to-valley compensation in the case where one linearreciprocating pump is drawing the fluid while the other linearreciprocating pump is compressing the fluid out.

The sampling pumps described in various embodiments of this disclosuremay also include multiple reciprocating pump sets. The multiplereciprocating pump sets may be separately arranged, or may also berigidly and fixedly connected to one another. In some embodiments, apart of the multiple reciprocating pump sets may be separately arranged,while the remaining reciprocating pump sets may be in rigid and fixedconnection to one another.

The sampling pump will be further illustrated from the followingdescriptions, where gas is used as the fluid and a linear reciprocatingpump is used as the reciprocating pump by way of example.

Referring to FIG. 4, a sampling pump may include a control system (notshown here), two linear reciprocating pumps 11, 12 and a connectionplate 2. Each of the linear reciprocating pumps 11, 12 can berespectively provided with an inlet nozzle 112, 122 as a fluid inputchannel and an outlet nozzle 111, 121 as a fluid output channel. The twolinear reciprocating pumps 11, 12 can be rigidly affixed onto theconnection plate 2, and thus the two linear reciprocating pumps 11, 12and the connection plate 2 may form an integral structure.

In this embodiment, the two linear reciprocating pumps 11, 12 may havethe same orientations. Based on this arrangement, the control system cancoordinate operation timings of the two reciprocating pumps 11, 12 viathe drive signals that have the same amplitude but opposing phase (i.e.,with a phase deviation of about 180°). In this way, movement directionsoutputted by the motors of the two linear reciprocating pumps 11, 12 canbe opposite to each other at any time. As a result, impact vibrationsgenerated along opposing directions by the two linear reciprocatingpumps 11, 12 can be counter-balanced (or mostly counter-balanced).

The outlet nozzles 111, 121 of the two linear reciprocating pumps 11, 12can further be assembled together to form an integrated output channel.Since the two linear reciprocating pumps 11, 12 may compress the gas outin alternate fashion, their alternating gas flows may combine tocorrespond to overlapping peaks and valleys. As a result, stable flowcan be achieved and fluid fluctuations can be greatly reduced duringfluid delivery.

FIG. 5 also shows an embodiment of this disclosure. Unlike theembodiment shown in FIG. 4, there is no connection plate in thisembodiment; instead, the two linear reciprocating pumps 11, 12 aredirectly, rigidly and fixedly connected along an axial direction to forman integral structure.

The sampling pumps described in various embodiments above can be appliedto any fluid analyzers or any fluid measurement equipment. For example,a gas analyzer with such sampling pumps can be provided.

In an example embodiment (such as FIG. 4), a gas analyzer can include agas measurement module and any one of the above-described samplingpumps. The gas measurement module can be used for gas detection andanalysis. Any existing or future techniques that can achieve gasdetection and analysis can be employed for the gas measurement module.The sampling pump can deliver the gas to be detected and analyzed from agas source to the gas measurement module.

The gas analyzer in this embodiment may also include a base 3 and one ormore gas circuits (not shown here). The reciprocating pump set can befixedly mounted on the base 3, and the gas circuit(s) can be fixedlymounted on or inside the base 3. The gas circuit(s) can include two setsof gas inlets 32, 34 and gas outlets 31, 33, where the two gas outlets31, 33 may communicate to form a larger gas outlet for gathering the gasoutputted from the two linear reciprocating pumps 11, 12. In thisregard, the two gas inlets 32, 34 may also communicate with each other.The gas sensor(s) within the gas analyzer is a precision instrument thatis not only sensitive to external vibrations but also to fluctuations ofgas flow. If the fluid has large fluctuations when passing through thegas sensor(s), measurement noise that affects measurement accuracy mayoccur. For these reasons, two reciprocating pumps having symmetrical(i.e., opposing) impact effects can be employed in this embodiment. Onone hand, impact vibrations can be reduced during operation so as torealize stable gas delivery and improve the measurement accuracy of thegas sensor(s). On the other hand, the sampling pump in this embodimentmay use alternative drive timings for gas sampling, in which case thegas can be outputted stably and flow fluctuations can be significantlyreduced from the gas circuit(s), thereby further improving themeasurement accuracy of the gas sensor(s).

In some alternative embodiments of this disclosure, two reciprocatingpumps within the same set may not be arranged along the same line.Instead, based on the technical solutions herein to solve the involvedvibration problem, any suitable arrangement can be used for the tworeciprocating pumps as long as their impact forces have opposingdirections so as to achieve absorption of vibration to a certain extent.

This disclosure is described above as detailed illustrations withreference to specific implementations, while this disclosure should notbe limited to these illustrations. For those of ordinary skill in theart, various conclusions or equivalents may be made without departingfrom the concept of this disclosure, while such conclusions orequivalents should be deemed to be included within the scope of thisdisclosure.

The invention claimed is:
 1. A sampling pump, comprising: at least oneconnection carrier; at least one reciprocating pump set comprising tworeciprocating pumps, wherein each of the two reciprocating pumpscomprises a rotary motor and an outlet nozzle, wherein the tworeciprocating pumps are separated and mounted on the at least oneconnection carrier; a base separated from the at least one connectioncarrier, wherein the at least one connection carrier and the tworeciprocating pumps are mounted on the base; a control system inoperable communication with each of the two reciprocating pumps andoperable for outputting drive signals to the rotary motor of each of thetwo reciprocating pumps, wherein the drive signals cause the tworeciprocating pumps within a same reciprocating pump set tosimultaneously provide opposing impact force directions; and at leastone integrated output channel comprising each outlet nozzle of the tworeciprocating pumps.
 2. The sampling pump of claim 1, wherein the drivesignals have identical amplitudes and different or identical phasesdepending on whether the two reciprocating pumps are in a same oropposing orientation, respectively, along a common line to cause the tworeciprocating pumps within the same reciprocating pump set tosimultaneously provide opposing impact force directions.
 3. The samplingpump of claim 2, wherein the two reciprocating pumps within the same setare in a same orientation, wherein the drive signals provided to each ofthe two reciprocating pumps have identical amplitudes and a phasedeviation of about 180°.
 4. The sampling pump of claim 2, wherein thetwo reciprocating pumps within the same set are in an opposingorientation, and wherein the drive signals provided to each of the tworeciprocating pumps have identical phases.
 5. The sampling pump of claim1, wherein the two reciprocating pumps within the same set are linearreciprocating pumps with an identical impact force.
 6. The sampling pumpof claim 1, wherein the at least one connection carrier is a connectionplate that is affixed to side surfaces of the two reciprocating pumps inthe same set.
 7. The sampling pump of claim 1, wherein the at least oneconnection carrier and the two reciprocating pumps forms an integralstructure.
 8. The sampling pump of claim 1, wherein the at least oneintegrated output channel communicates to each outlet nozzle of the tworeciprocating pumps within the same set.
 9. The sampling pump of claim1, further comprising at least two gas outlets mounted on the base. 10.The sampling pump of claim 9, wherein the at least two gas outlets arecoupled to the at least one integrated output channel to gather a gasoutputted from the two reciprocating pumps.
 11. A gas analyzer,comprising: a gas measurement module for gas detection and analysis; anda sampling pump for providing the gas measurement module with gas to bemeasured, wherein the sampling pump comprises: at least one connectioncarrier; at least one reciprocating pump set comprising tworeciprocating pumps, wherein each of the two reciprocating pumpscomprises a rotary motor and an outlet nozzle, wherein the tworeciprocating pumps are separated and mounted on the at least oneconnection carrier; a base separated from the at least one connectioncarrier, wherein the at least one connection carrier and the tworeciprocating pumps are mounted on the base; a control system inoperable communication with each of the two reciprocating pumps andoperable for outputting drive signals to each rotary motor of the tworeciprocating pumps, wherein the drive signals cause the tworeciprocating pumps within a same reciprocating pump set tosimultaneously provide opposing impact force directions; and at leastone integrated output channel comprising each outlet nozzle of the tworeciprocating pumps.
 12. The gas analyzer of claim 11, wherein the tworeciprocating pumps within the same set are linear reciprocating pumpswith an identical impact force.
 13. The gas analyzer of claim 11,wherein the drive signals have identical amplitudes and different oridentical phases depending on whether the two reciprocating pumps are ina same or opposing orientation, respectively, along a common line tocause the two reciprocating pumps within the same reciprocating pump setto simultaneously provide opposing impact force directions.
 14. The gasanalyzer of claim 13, wherein the two reciprocating pumps within thesame set are in a same orientation, wherein the drive signals providedto each of the two reciprocating pumps have identical amplitudes and aphase deviation of about 180°.
 15. The gas analyzer of claim 13, whereinthe two reciprocating pumps within the same set are in an opposingorientation, and wherein the drive signals provided to each of the tworeciprocating pumps have identical phases.
 16. The gas analyzer of claim11, wherein the at least one connection carrier is a connection platethat is affixed to side surfaces of the two reciprocating pumps in thesame set.
 17. The gas analyzer of claim 11, wherein the at least oneconnection carrier and the two reciprocating pumps forms an integralstructure.
 18. The gas analyzer of claim 11, wherein the at least oneintegrated output channel communicates to each outlet nozzle of the tworeciprocating pumps within the same set.
 19. The gas analyzer of claim11, further comprising at least two gas outlets mounted on the base. 20.The gas analyzer of claim 19, wherein the at least two gas outlets arecoupled to the at least one integrated output channel to gather the gasoutputted from the two reciprocating pumps.